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Stochastic Light-Cone CTMRG: a new DMRG approach to stochastic models

A. Kemper·A. Gendiar·T. Nishino·A. Schadschneider·J. Zittartz
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Abstract

We develop a new variant of the recently introduced stochastic transfer-matrix DMRG which we call stochastic light-cone corner-transfer-matrix DMRG (LCTMRG). It is a numerical method to compute dynamic properties of one-dimensional stochastic processes. As suggested by its name, the LCTMRG is a modification of the corner-transfer-matrix DMRG (CTMRG), adjusted by an additional causality argument. As an example, two reaction-diffusion models, the diffusion-annihilation process and the branch-fusion process, are studied and compared to exact data and Monte-Carlo simulations to estimate the capability and accuracy of the new method. The number of possible Trotter steps of more than 10^5 shows a considerable improvement to the old stochastic TMRG algorithm.

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A. Kemper, A. Gendiar, T. Nishino, A. Schadschneider, J. Zittartz. 2002-10-22. Stochastic Light-Cone CTMRG: a new DMRG approach to stochastic models. https://doi.org/10.1088/0305-4470%2F36%2F1%2F303

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